Acetone smell in well-fed starter
I've been working on my first sourdough starter for almost two weeks now (it'll be two weeks on Sunday). Things were going well initially, and around day 3 or 4 I started feeding it every 12 hours. It got that nice, tangy smell but never rose much at all. I just kept feeding it every 12 hours, waiting for it to start doubling, and two days ago it started to smell strongly of acetone. I know this is common, and from my searching it seems that it is usually a symptom of a hungry starter. I fed it as usual yesterday at 7:30 am, and called King Arthur Flour's baking hotline yesterday afternoon around 3 pm. They suggested to go ahead and feed as usual right then (dump all but 4 oz and feed with 4 oz of unbleached AP flour and 4 oz of spring water), and see if the smell went away by that evening.
It did not. I'm in central Texas and it is still quite warm here, so my kitchen gets up to 77 during the day, and we keep the a/c around 70 at night. I thought that maybe the warmth was causing the yeast to consume all the flour nutrients too quickly and that giving it a third feeding during the day would help, but it doesn't seem so. I then thought that maybe I could add a tablespoon or so of whole wheat flour to my usual AP flour (still keeping the total at 4 oz), in the hopes that it would help the yeast become active enough that I could start storing it in the fridge. I did this last night, and it did indeed rise a little more (maybe 50%), but it still smells like acetone.
Any suggestions? Should I just keep feeding as usual and wait it out? I'm happy to be patient and am in no hurry, but I'd just like to know if I need to do something in addition to my usual feedings to get this smell to go away.
If your starter is active, and the weather is warm, a 1:1:1 mixture will not last long - that's a lot of starter, and not a lot of food. If it's not that active, and isn't bubbling, I would simply continue and wait it out.
Oh it's bubbling, just not doubling. I'm at work during the week and can't feed it much more often than every 12 hours for that reason. What ratio would make it last longer?
My starter frequently smells of acetone, but it does not persist through the baking. When I wnat to bake, I take the starter out of the refrigerator, feed 1:1:1 (by weight) and let it sit for eight to twelve hours; feed again 1:1:1 and let it sit overnight and it is ready to make bread then.
Ford
I tend to feed once every 24 hours, and I don't refrigerate - a ratio of around 1:10:10 works for me.
I wouldn't expect a 100% hydration mother/starter to double in volume. It's just too wet; the bubbles rise through the paste.
Try a 1:2:2 feeding ratio. Ketones are formed when the little beasties are out of sugar and start using fat for food; in other words, during fasting starvation. I don't think it's fasting if it's not by choice. ;-) The ketones, instead of being re-absorbed in the presence glycols, are converted to acetone which is expelled in respiration.
cheers,
gary
Interesting! The KAF blog post on making a starter made it sound like no big deal for a 1:1:1 starter to double at some point. So tonight I think I'll try maybe 2 oz starter:4 oz water:4 oz AP flour. Do you think that'll work? Should I keep adding a bit of whole wheat flour as well?
And I think most others will disagree with you as well. A 100%-hydration, AP flour starter is definitely stiff enough to double. My 100%-hydration whole wheat starter would almost triple.
Same here. 100% triples almost everytime... It's not too liquid for the bubbles...
There will be a little lift, but nowhere near a doubling of volume. This is true for AP, BF, WW and Rye. 100% hydration gives a thick batter-like consistency that will not support much rise.
cheers,
gary
I will offer a photo as data that supports at least doubling (this is close to tripling but I have never actually checked). This is a 100% hydration starter after 11 hrs @ 22°C; it is past its peak and ready to be refreshed again. Initial mix was 5 g starter + 14 g water + 14 g of high gluten flour and was at the bottom of the blue tape when freshly mixed. The container is a 5.5 oz polypropylene food service cup with matching lid; it is slightly tapered so a doubling of height is a more than doubling of volume.
Thanks for the great info. When you give a ratio, is it starter:flour:water?
That's right, once your starter is stable, you'll quickly get a feel for how long it takes to 'mature'. It's surprising how quickly 5g of active starter will consume 100g of flour, at 21C!
Another option in that warm weather is perhaps moving to a stiffer starter, which would progress slower than a liquid one, and perhaps keeping it in a cooler part of the house. A stiffer starter also encourages more yeast growth and a bit less bacteria growth. When I lived in San Diego I used my closet, which was dead center of the house and didn't get as warm (no AC), staying about 5-7 degrees cooler than my hot kitchen (curse you south facing windows!)
So, it's just about doubled tonight at exactly 12 hours since its last feeding, but still smells of acetone. (It's currently a 100% hydration starter, so they can indeed double.) I added 1 tbsp of whole wheat flour to the last two feedings, which I'm sure helped it rise. I'm going to try a 1:2:2 feed tonight and see if I can still get a rise without the smell.
This is an essential step for your starter. Now ignore the acetone (and "double") for a little while, you got some rather hungry happy bugs in there eating like crazy. We don't know if they are bacteria or yeasts but we can narrow down the playing field using salt and the refrigerator. Let's make the bugs we don't want uncomfortable.
With the next morning feeding give it a pinch of salt and stick to the 1:2:2. You got hot temps this week (wow, hope you don't melt in TX.) After the peak (not double) chill the starter. Stick it into the fridge overnight (or a day and a half) and remove tomorrow. Then discard and feed 1:2:2 with pinch of salt until it peaks (let's hope it is less than 12 hours) chill again at the peak. Repeat until your peaking is down to 8 hours. When the starter can peak in 8 hours or less, give it a 1:4:4 feed without salt and see what it does. Chill at the peak while checking for acetone smells.
If acetone smell is gone, use some, bake a loaf or pancakes and feed (1:4:4) again putting a pinch of salt in the mixture. Let rise for a few hours and chill. This will keep for several days or a week in the fridge. Take a rest. For the next bake remove some of the starter from the chilled supply and feed for a build to use in baking. Keep salt in the starter until your temperatures drop to the high 70's or you find it slows down fermentation too much.
Mini
Argh, I didn't see this until after this morning's feed. I ended up splitting the starter into two jars last night - in one I did my normal 100% feed, and in one I did a 1:2:2 feed. Figured I could get scientific about it and conduct a comparison. After a few hours I sniffed and the 100% one actually smelled tangy, with no acetone, but by morning they both smelled like acetone again. Boo. Neither had doubled. I keep the a/c at 70 at night.
I guess tonight I can start with the pinch of salt feed as you describe above. I wish I was around the house more during the day during the week so I could keep a close eye on peaking. It's only going to be in the low 90s this week (ha, that is pretty darn pleasant for around here) but I keep the thermostat at 77 in the house during the day, and it probably won't consistently be in the 70s during the day until November or so.
I want to make sure I understand the ratios. A 1:2:2 seems pretty straightforward - that would be something like 2 oz starter:4 oz flour:4oz water, correct? But when I see something like a 1:12:12 or 1:40:40, it seems less straightforward. What are actual weights you'd use for a ratio like that?
Read the caption at this link:
https://picasaweb.google.com/lh/photo/fi-e1pO54wPQ6mzMGGfaqNMTjNZETYmyPJy0liipFm0?feat=directlink
they are all 100% meaning 100% hydration or weight of water equal to the weight of flour. So a 1:1:1 is 100% but so is a 1:2:2 and so is a 1:4:4 and so on. So when you mention "the 100% feed" I'm not sure which one you are talking about. the "1" in the ratio can be one oz also. It can also be 1/2 oz. That would make a 1:2:2 (s:w:f) 1/2 oz (or .5 oz) 1 oz water and 1 oz flour. Keeping it small might cut down on waste. Cover to prevent drying out.
Ok, I see something now... you got cold temps at night and warm during the day, and you are hoping for a good rise when the temps are low around 70°F. This is not good. Do not feed at night with cold temps. You fed the starter already for today. When it peaks, chill it. Remedy the situation so that the starter is fed in the morning and rising when it is warm, while at work. When you get home look at the edge of the glass to see if it rose during the day. Then wait for the peak if it hasn't happened yet. If it did peak, pop it into the fridge and feed a reduced starter in the morning. :)
Ohh, that makes sense. I was thinking that a 1:1:1 was the only 100% hydration starter, but I see now that other ratios can also be 100%. Thanks for clearing that up. I'll also try your suggestions regarding refrigerating it. I'm seeing that I should probably clean my jar so I can tell if it peaks. :) Thanks so much!
At 12 hr intervals you want to be refreshing at about 1:12:12 (starter, water, flour).
But to get rid of the acetone smell you want to do a 1:40:40 and let it go for ~16 hrs at the same 23°C (maybe twice).
Stiffer starter will grow to more than double (i.e., 1:10:15) before it starts to decline. Whole wheat flour tends to behave as if it is more flour than if it was white.
Don't worry about it. A 1:20:20 will go 24 hrs @ 23°C and not die and not smell like acetone but you don't want to do that too often or the microbiology will shift on you and you will have a new (different) starter. In the winter it will be a different number because the temperature will be lower.
The boiling point of acetone (aka: dimethyl ketone, or 2-propanone) is 56.2°C (133°F). Thus it readily evaporates when the bread is baked (internal temperature 190 to 200°F or 87.8 to 93.3°C). My starter frequently smells of acetone, but my bread never does. Don't worry about a little acetone in your starter.
Ford
Thanks for the reassurance! Is it actually acetone, though? Yikes - I thought it was something less toxic that just smelled like acetone. Ethyl acetate, maybe?
Ethyl acetate does not smell like a ketone. It is an ester. Esters have their own characteristic smell.
Acetone and ethyl acetate are of comparable toxicity.
Acetone: LD50 for rats 10.7 ml/kg
Ethyl Acetate: LD50 for rats 11.3 ml/kg
Source is the Merck Index.
This means that if you weigh 110 lb and the toxicity is the same for you as it is for rats, were you to drink about a pint of either compound, you have a 50% chance of dying. That would be a lot of sourdough starter for you to consume.
Ford
Which is why both chemicals are used in nail polish remover, a material used by many non-technical people. *grin*
I know you're all waiting with bated breath for my update (ha) so here goes. I tried Mini's suggestion above this weekend. It smelled better but was still getting acetone-y when it peaked. Today I fed it as usual in the morning, but by the time I got home from work, about 10.5 hours later, it had already peaked and was sinking, smelling very strongly of acetone. Sigh. Since it's not getting any cooler around here any time soon, I anticipate not being home during the week when it peaks and therefore won't be able to refrigerate it then. Flying by the seat of my pants, I decided to try a 1:3:3 feed overnight (on my counter) to see what happens. (I have been doing 1:2:2 feeds.) My line of thinking was that if the smell is resulting from the yeast consuming its food too quickly, giving it a bit more food might help. I have no idea if this will actually work. Also, I forgot to add a pinch of salt as Mini suggested - can someone tell me what it does here?
The acetone smell was back two hours after the refresh, but I guess we'll wait and see what things look like in the morning. It hasn't really doubled again since that one time this weekend. Today is day 15.
http://www.thefreshloaf.com/node/10359/discouraged-southeast#comment-54426
Maybe you should start over while waiting for this starter to come around. It's only been three days, give it a week. And do try the salt.
If you don't see an improvement with larger feeds (more flour to starter ratios) or every 8 hour feeds (it must rise and fall) then you won't be able to get rid of the bugs that are causing this mess. I recommend the above method posted by Debra Wink. This is posted on a discussion of acetone like aromas coming from a starter.
Thanks - I read over her original posts on the pineapple juice starter yesterday and was considering trying that out anyway. This morning I gave it a bit of salt so we'll see what happens. I really appreciate everyone's help here.
In my opinion, there is no reason to start over. Just keep on feeding. When you get an active starter, try a loaf. You will get no acetone nor ethyl acetate odor in the final loaf. This odor is no big deal. After your starter is matured, your bread will taste just great! Give it three to four weeks. tarting over will just delay things.
Ford
Today when I got home I noticed that the smell, while still fairly strong upon removing the plastic wrap from my culture jar, started to dissipate pretty quickly. It was very faint after I stirred it down, and I tasted some and it was pretty tart/sour but not bitter (as it had been the last couple of days), so I guess that's good! It had also doubled. I refreshed and we'll see what kind of action we get tomorrow morning. Honestly, I'm more bothered by the fact that it takes a minimum of 12 hours to double than the fact that it smells, but maybe that'll just take time.
So right now I'm still adding a spoonful of whole wheat flour in with the AP when I refresh. Should I expect to keep doing this forever, or will it one day be strong enough to double on its own with just AP flour?
I keep two starters, one whole wheat and one all-purpose flour. When I want to make rye bread, I use one or the other and build with rye flour. I believe that you will do just fine to build using only the all purpose flour and chlorine-free water. Yes, my 100% hydration starter will double, or triple within three hours, after being refreshed. Have patience your starter will mature.
Ford
I tend to get so excited! The salt is slowing the fermentation and yeasts as well. That it takes longer to peak is "OK" for the next few days. But do let it peak before chilling. Drop the salt when the acetone smell is gone for about two days. Then be prepared for some rapid rising. :)
@Mini - are you assuming the the salt is inhibiting the source of the acetone-like smell? Or that the source of the smell is the dominant yeast in the culture and you are just slowing the whole thing down (rather than driving the feeding ratio up)? The feeding ratios seem very small to me for warm weather propagation.
Several things to consider before jumping to sky high ratios (1:12:12) or (1:40:40) Feel free to debate anything.
The starter was only 2 weeks old at the time of the posting, now 3 weeks and the acetone producing beasties are having a free for all feeding festival. By slowing everybody down in the starter, I'm hoping the dominant aggressive acetone producing beasties will be at a disadvantage. Hopefully enough to let other beasties increase their numbers and hopefully push out the overactive acetone ones. Don't know why the beasties are metabolizing so fast as to destroy maybe other good wee beasties (the ones we want) but giving them all the same playing field should boost yeast that tolerates salt. Keeping the whole wheat or introducing some whole berries will hulls or a spoon of coarse rye in the formula may help introduce new beasties. That is more or less up to the poster.
The air-conditioner is also playing a role. Feeding at night and leaving the starter out in the cooler temps below 75°F has been tried and failed. It might have encouraged the quick metabolizing beasties in the first place. So my suggestion is to upset the starter so it can reset and not feed it before chilling. It will be fed the next morning so the starter should not suffer hunger. Let the lactic acid producing beasties get a jump protecting and producing a safe guarding acid level. Raising the feeding ratio before the culture is stable could be too much for the starter. One might as well start a new starter and eliminate the acetone producing beasties altogether. The acid levels would be so diluted that another problem might arise or the same one encouraged. A stable starter where the dominant cultures have established themselves can take a lot more feeding abuse and higher feeding ratios than a new starter. This culture is still battling for the dominant supportive beasties inside itself. It needs a predictable schedule but one that is very different from the past but still within starter survival limits.
By choosing a pattern of higher room temp and then chilling, the pattern is set for Texas weather changes. What do Texans say? "If you don't like the weather, stick around for 6 hours, it will change." Texas weather requires a lot of flexibility in starter feeding. Get to know the starter, use the clock but only as a guide, not as a rule. Good is when the starter can be fed, allowed to propagate yeast for a few hours or about 1/3 peaked and then tucked into the fridge and be ready to use for the next few days. Just make sure it peaks or near peak before using. The starter needs to be established and stronger first before getting into this routine. I expect to hear more from Texas TFL members.
Acetone smell is not desired. It really kills creative thoughts too! (not like tangerine scented turpentine) It would be good to compare it to the smell of acetone nail polish remover just to be sure it is acetone and not closer to vinegar.
Thank you for the in-depth explanation! The smell is definitely acetone-y and not vinegar-y. I have done a 1:3:3 feeding the last couple of days with the same results as before and I stopped adding the spoon of wheat flour. Didn't want to go crazy with a bunch of variables. I'm still holding out hope that this starter comes around. It's like having a pet. I was watching a lot of Breaking Bad (popular TV show here in the US) when I started it and thus named it Hank. Now that I've named it I really don't want to give up on it. :)
@Mini,
Your advice is great, I just didn't understand what the rationale was. Now I do.
The cycle for a mature starter is always for the LAB to outgrow the yeast, acidify the mixture and stop reproducing. This leaves the acid tolerant species that remain to fight it out for the remaining sugars (typically glucose and the residual maltose not consumed by the LAB). In this case, it seems clear that the LAB are doing well and it is the yeast that is potentially the root of the problem. Since all growth rates are exponential in temperature within the bounds of species survival, I don't expect that temperature shifts are likely to be severe enough to move out of one species zone of tolerance and thus favor the one we want. Salt on the other hand is a variable that I don't really have a quantitative handle on. Ganzle discusses ionic strength in his dissertation but I have never been able to do the calculations in a way that gets the same answers that he did so there is still something missing in my understanding. My thought was that if the sugars are being so severely depleted that alternate substrates are being used and thus producing acetone (or similar ketones), then more food or at least enough so that the starter does not peak until it is time to feed again might prevent the occurrence of conditions that force a metabolic path that produces the stuff we don't want. Required refresh ratio for a fixed inter-feeding time is of course a strong (exponential) function of temperature. I see adding salt as equivalent to increasing the refresh ratio unless there is a specific differential growth rate effect which is what I think you are looking for.
Day 18. This is my little buddy 13 hours after feeding this morning. The red is where I marked where it was just after feeding this morning. You can see that it hasn't risen much.
Here's a bubble shot - it's actually quite bubbly:
This was a 1:3:3 feed with KAF unbleached AP flour and bottled spring water, as usual. It was around 77 most of the day. I have not done the salt + fridge thing in a couple of days, as I am not home most of the day and I really can't tell if it has peaked or not. When I get home I usually get a strong whiff of acetone upon opening it, which makes me think it has probably peaked and burned through all the flour, and I'm wary of popping it in the fridge at that point without giving it another feed first - is that a good line of thinking?
So I've really got two separate things going on here that I'm trying to resolve. One is the smell, and the other is the fact that it doesn't double consistently within a reasonable amount of time (12 hours or less), and I guess I need to figure out which to try to remedy first, right? I was doing a 1:2:2 feed, and moved to the 1:3:3 along the same line of thought as Doc Dough, that maybe it just needed more food. I thought about moving up to a 1:4:4, but wasn't sure if that would be too much for an immature starter.
But this looks like a starter that rose and fell already. You have got to clean it's cage! The sides of the jar said it rose unless they were this coated already. I like to run between two jars. feed the starter and pour into a clean jar to see if it does rise up the sides when I'm not looking.
The salt treatment was to be a constant for every feed, not just one time, until the acetone aroma was completely gone. Sorry I didn't make that clear. It is probably too late now. Although we are all a bit curious how that would come out.
If I were you, I'd start a new starter and make it unsweetened pineapple juice instead of water.
I'd actually like you to dry some of this ripe acetone starter on a coffee filter or paper towel. You've got plenty of discard, cut the filter paper slightly smaller than an envelope and keep it away from your new starter. Wrap it in a sheet of paper and send it to me in an envelope. I will try to duplicate your conditions and see what happens and how to change them. Ha! a diagnostic first! Maybe DocDough would also like a sample. Then we could test out our theories against each other. Might be fun. I will send you a personal message with address.
Mini
I am jumping in here late and haven't read all comments so forgive me if I repeat something someone has already said.
When my starter is too wet it smells...not sure what acetone smells like but the smell I get isn't nice and is usually evident within the first day or 2 of starting up a completely new starter.
What I have done in the past that has worked is to decrease the hydration. So if I was in your shoes at this point I would try dropping the hydration level to 65-70% instead of the 100% where you have it now so a feed might be 10g seed: 21g water: 30g flour but if I were to feed that to my starter it would double in about 6 hours with the temps you are having....
Also, doubling isn't always what happens. What I look for is when my starter reaches it's 'peak'. For a firm starter it won't double before it reaches it's peak and starts to decline.
My comments aren't based on anything scientific. Only what I have done with my starter and I am still fairly new to sour doughs - only about a couple of years so I am still learning lots by making new starters and experimenting with quantities and temperatures. One thing I do know is that what works for me is when I begin to smell the 'off' smell.....less water.
I also have to say that my starters are made with 100% whole grains that are freshly milled so my results may be very different than yours are due to the amount of enzymes present in my flour...
Hope this doesn't confuse matters....
Good Luck,
Janet
P.S. I should mention that I didn't even attempt starting up my own sd from scratch until I had been baking with one I ordered off line for a good year....Didn't think I could do it and had no idea what to expect so by ordering a 'live' one and working with it for awhile I had a pretty good idea what I was looking for. (I.E. I cheated :-) but it worked and got me to where I am today!)
My read on your situation, from the acetone smell and the picture of your starter, is that it is rising plenty during the day while you are gone, but then falling back down so that when you come home it looks like it didn't double. Seems like it needs more food, which in essence is what both Doc and Mini are saying. In order to see how much it has risen, you'll need to put it in a clean jar with clean sides at every feed, then look for a high-water mark to see how high it got while you were away. As long as you are seeing a high-water mark, it is past its peak and needs more food. Carefully increase ratio of flour + water to seed until you get a peak around the time you next want to feed it. I agree both with the suggestion to switch to a lower hydration starter (easier to see the peak) and with the suggestion to maintain salt in feeds.
I kept my firm starter salted all summer, 1/8 tsp salt for a feed of 5g seed, 30g water and 50g flour. Now that our weather is cool, I've ditched the salt and increased my seed to 10g.
Why didn't I think to post pics at the beginning? Ok, this morning I put it in a clean jar with a bit of salt so we'll see what happens during the day today. Mini, I'm happy to send you some dried bits - shoot me a message and let me know where to send it. Also, can you clarify on the refrigerating - is it ok to refrigerate if I get home and it's obvious that it has peaked and gone down already? Or does the refrigeration need to be done pretty quickly once it peaks?
I think I'm going to get some pineapple juice and start another one that way, but still work on this guy. I've put too much effort into it to give up just yet.
the only time you wouldn't chill it is if the sides of the glass jar are still clean, then wait to see if it rises more and chill.
I'm looking for my crystal ball to see where I am in two weeks. Will shoot that address asap. I got all tied up today with a dead car battery. If only it was a starter! [+-] :)
Here's what we have. There was no peaking after 12 hours yesterday so I thought I'd let it keep going. This is from this morning, 24 hours after the last feeding. Still no peak from what I can tell (after 24 hours!), but tons of bubbles and strong acetone smell.
Ha! I'm close to throwing up my hands but will maybe try a stiffer mixture and keep including a little salt for a few days and see what happens. Mini, I'll dry you a sample and send it out. Thanks again, everyone, for your advice. I'm not new to bread baking but this sourdough business is something else!
It looks like your rise was about 1.5x, but not double. Good job putting it in a clean jar so that we can see what's going on!
How much did you feed it?
It looks liquid enough that bubbles are popping at the surface, is that right? It's possible that gas is being produced, but not contained. Is your flour a lower-protein flour? That would make a difference in whether a starter fed 1:1 flour to water will be thick enough to hold on to its bubbles. Try a stronger flour (12% protein) or a little less water.
Did it continue to rise overnight? Or was the level unchanged from the 12-hr mark?. Doesn't look as though it fell/sank lower by morning.
The smaller rise could be from a combination of not enough food (didn't have enough food to sustain a larger rise) and bubbles popping. If it were me, I'd try feeding it 1:3:2 (seed:flour:water) and see what happens.
It was a 1:3:3 feed. It didn't really rise much overnight. I'm using KAF unbleached AP flour. This morning I made it stiffer - 10 g starter, 100 g flour, 60 g water, plus a pinch of salt. That was at 10 am, and right now (12:30 pm) it has already puffed up quite a bit and smells sour, with no acetone smell! (Whoever asked above - acetone smells like nail polish remover.)
Crossing fingers!
Woo hoo! It doubled 9-10 hours after feeding and is peaking now from what I can tell, 11.5 hours post feeding.
If you look closely enough, you can see the dome. Also, there is nary a whiff of acetone! Finally, something is working!
of feeding that you are now using. :) That is good news!
Looks good! I ran an experiment yesterday by making two different refreshed samples (both at 1:14:14) from starter that was 26 .5 hrs old an 16 hr old. The 16 hr starter was still falling but the older one had fallen completely but still had plenty of small bubbles. They behaved as twins until the container with the older seed peaked and began to fall sooner. Conclusion: the yeast population was still increasing between 16 and 26 hrs. So picking the precise time to feed is not too terribly sensitive once it has peaked since the yeast repopulation density has a very broad peak that does not exactly mirror the rise and fall of the starter.
I have photos if anybody is interested
That's great info, Doc! Please post pics!
Patience pays. After you are satisfied that your starter hasw matured, spread a thin layer of starter onto some parchment paper and let it dry at room temperature. Place the dried flakes in a labeled, plastic bag and store it in a cool place. These flakes can then be reconstituted with some fresh flour and chlorine free water to make a new starter in the case of a disaster.
Ford
Thank you again for all the help, everyone. I've refreshed since my last post and everything still looks good, so hopefully we're ok for now. :)
The photos documenting the experiment I mentioned above are at the following link:
https://picasaweb.google.com/117028767311163668653/CompariativeStarterGrowth?authuser=0&feat=directlink
I am including only three pictures here but you can see the full set by following the link.
This is the initial condition:
A batch of starter was refreshed on Thursday AM at 1000 (at somewhere around 1:14:14) and let ferment on the counter for 10.5 hrs at which time it was then used to seed a new refreshment at ~1:14:14 at 2030 on Thursday night. Sixteen hours later (1230 Friday) two new batches were initiated with these as seed cultures. The older seed culture had been sitting on the counter for 26.5 hrs since being fed at 1000 Thursday while the younger one was 16 hrs old. The younger starter is on the left and the older one on the right in the photos.
This is the last photo I took before getting distracted on Friday night:
You can see that they are essentially growing at the same rate.
Overnight they peaked and began to fall back. Here is the early morning shot on Saturday after 18:43 elapsed time. You can see that the older starter peaked earlier and began to recede while the younger one took a while longer to explode the foam and fall. Conclusion: a healthy, active starter is viable for quite a while after it reaches peak volume and in fact may have a higher yeast cell population density quite some time after it begins to fall back - not due to running out of food, but simply because the foam is not strong enough to contain all of the gas being produced by the yeast.
Comments, alternate explanations, and experimental critiques are welcomed.
Doc, thanks for those- they are great and are consistent with recent shenanigans in my starter. More details on that in another thread but basically recent events have led me to the conclusion that for ongoing starter maintenance (not for bread builds), it is important to err on the side of feeding after the peak rather than before.
Hi all! So after much work on the starter that got this thread going, (close to two months of work), I finally declared it a dud and tossed it. It would just never double consistently within a reasonable amount of time and/or always smelled funky. Work got busy and I gave up on starter making, and was close to just ordering some from KAF when I received Peter Reinhart's Whole Grain Breads for Christmas. It got me thinking about the pineapple juice method, so I decided to give it a go.
Lo and behold, within 5 days I had a vigorous starter! I made the 100% whole wheat bread with it, and it tasted wonderful! That first loaf had some room for improvement, and the second try was much better:
I now have a sourdough loaf in the works that's only being leavened by the starter. We'll see how it goes! Anyway, I just wanted to update and say thanks again to everyone who helped me, and thanks to Debra and team for coming up with the pineapple juice method. I just gave some extra starter to a friend who's hoping to get into sourdough. I love the community that forms from bread baking, both in real-life and here online. :)
Hi Slog…
I am so please to see that you worked through some major challenges and came out successful on the other end. I have read through this string… there is a LOT of content here. With various opinions and defenses and challenges. There is also a good combination of Biochemical Theory and Lay Wisdom.
I have had similar struggles with my starter. The acetone smell, the bubbles with no rise.
Could you provide a synopsis of what you actually did to move your starter from the Weak-bubble, Acetone-smelling mixture to a robust, bread-worthy one?
Thanks
Well, as I mentioned in my last post in this thread, I had to toss the starter that made me start this thread. The one I'm working on now was started with the pineapple juice method. I actually started a thread about it a few weeks ago (called "my starters don't like white flour" - I think it's on the front page of this subforum now) because it was starting to act very sluggish when fed with only white flour. Taking the advice of the posters in that thread, I gave it a 1-1-1 feeding and let it sit for a while. After 48 hours, it hadn't doubled but was very bubbly and acetone-y. Basically for the last several days I've been feeding it, letting it go till it's really bubbly and active, then feeding it again. I started with a 100% hydration feed, but once it got more active I had to move to a 75% feed because it was getting the acetone smell before it could rise well.
Finally, today (probably 5 days or so from when I first started this round of revival attempts), it doubled in about 8 hours. I waited 12 hours, and there was no acetone smell but it was a little more than doubled. The key proportion now is 1-3-2.25. I also keep it at a really steady temp - in my oven with the light on. I'm not sure what the exact temp is, but I'm guessing high 70s F. The steady temp helps me to better gauge whether or not my flour/water proportions are working without worrying about temp fluctuations affecting anything.
So, that's where I am today. I'm cautiously optimistic. We'll see if it doubles again within a reasonable time. I've learned that constant trial and error is the only way I can figure out what works with my starters. If you're up for it, I would get two or three different feeds going at the same time to try out a few different hydration levels and see if one strikes your fancy. I work full time and have two kids, so this is a little much for me, but if I had more time this is what I would have done. Good luck!
I am on day two of my ten day starter and this is my first time doing a starter. My starter is active and gets a lot of air and bubbles in it but have a very strong acetone (nail polish remover) smell. My place is kept at 69F during the day and 68 at night. Should I feed it or just wait until day six to feed my starter. I did mine with active dry yeast that I bloomed in 110F water, milk, flour and sugar according to an Amish recipe I found online.
However the advice for an acetone smell in a sourdough starter made from flour and water is to feed it out. I would normally advise to increase the feeds until the smell dissipates but it's also important to only re-feed when there is activity. Bearing this in mind I think you should be feeding more regularly with higher ratios when peaked.